Apparatus unit



Sept 9, 1930- w. M. BAILEY 1,775,266

' AAPPARATUS UNIT Original Filed Oct. ll 1924 5 vwantoz Patented Sept. 9, 1930 UNITED STATES PATENT OFFICE WILLIAM M. BAILEY, OF LYNN, MASSACHUSETTS, ASSIGNOR TO WIRELESS SPECIALTY APPARATUS COMPANY, 0F BOSTON, MASSACHUSETTS, A CORPORATION OF NEW Y0 RK APPARATUS UNIT Original application filed-October 1, 1924, Serial No. 740,925. Divided and this application led June 14,

1926. Serial No. 115,823.

rlhis application is a division of my application, Serial No. 740,925, ined Oct. i, i924.

This invention relates to apparatus unit.

The object of the invention is to produce an improved device of the above nature.

The invention consists of the improvements in construction disclosed herein and illustrated in the drawings, of which Fig. 1 is a diagrammatic view of certain electrical condenser sheets; i

Fig. 2 is a plan of such condenser at a stage in the process of manufacture for use in accordance with the invention;

Fig. 3 is a plan of the sheet condenser as completed for embodiment in the invention;

Fig. 4L is an end view, enlarged, of the Condenser of Fig. 3;

Fig. 5 is a perspective of an electrical resistance completed for embodiment as an elej ment of a complete form of the invention;

Fig. (i is an elevation of the temporary assembly of the condenser and electrical resistance, in a part of the process of manufacture previous to permanent assembly;

Fig. 7 is another incomplete assembly, showing as located inside a glass tube, the assembly in 6 of condenser and resistance; Fig. 8 is a view similar to Fig. 7 showing the process of completing the assembly as t0 one end of the device;

Fig. 9 is a view similar to Figs. 7 and 8, wherein the partially assembled device of Fig. 8 has been inverted, to complete assem-r bly at the lower end of the device in Fig. 9; and

Fig. 10 is an elevation showing the completed invention as it may be used in practice.

rFhe condenser first will. be considered in connection with Figs. 1-4. While the condenser niay be of any. desired construction. suitable for use as an elementof the invention, yet the one here disclosed is suitable and at present preferred. The condenser is a sheet condenser consisting of sheets of dielectric and conductors alternately placed in a stack. The dielectric sheets may be of paper, oil saturated preferred to increase the dielec-4 tric strength. The conducting sheets may be of tinfoil. The condenser consists of four sheets, two of oil paper and two of the tinfoil, assembled alternately in the stack (Fig. 1). On the bottom is a paper sheet P2; above that is a foil sheet F 2; above that is a second paper sheet P1; and on top is a foil sheet F1. These sheets preferably are olfset endwise in the manner shown in Fig. 2. The sheets are shown separated, for clearness. When the sheets are laid on top of one another in the stack, they are to be rolled together in a cylinder as indicated in Fig. 1, the top of the stack being inside of the roll condenser, and the bottom (the paper sheet) being the outside of the roll. The condenser stack is shown in plan in Fig. 2, which shows that the two foil sheets F1,'F2 project from opposite ends of the stack. Three edges of each foil sheet lie, as shown,'a substantial distance inside of the edges of the adjacent paper sheet. As indicated in Fig. 1, this stack is to be rolled into a cylinder, beginning at the right-hand side of the ligure and rolling toward the left. `The rolled condenser is shown in Fig. 3. The left-hand edge S of paper sheet P1, as shown in Fig. 2, is shown in Fig. 3; in fact, the line S indicates the lefthand edges of both paper sheets P1, P2, (Figs. 1 and 2) and these edges of both paper sheets preferably are secured as by sealing-wax at S, to the adjacent surface of paper sheet P2 as wound into the roll, but partially exposed on the outside thereof. As shown in Fig. 3, the foil sheets F1, F2 extend as tabs at the two ends of the condenser beyond the paper sheets, these foils respectively being now wound in cylindrical shape as contrasted with Fig. 2 before rolling. Fig. 4 is an end view of the condenser of Fig. 3; but as a modified form of the invention it includes a centrally-disposed electrical resistance GL to be described now.

The preferred form of electrical resistance for combination with the above condenser in tube GT is shown in perspective in Fig. 5. Said resistance GL may be adapted in value as a high resistance for use as the grid leak of a. radio receiving apparatus; and in such case the condenser of Figs. 1-3 may be adapted as to capacity value as the grid condenser of such radio apparatus. In such case, the condenser may have a capacity of .0003 mfd.; the paper sheets P1, P2 being approximately four inches long by an inch and a quarter wide; and the foil sheets F1,

F2 being about three inches long by one inch wide. ln such case also the electrical re- 5 sistance of Fig. 5 may have a high value such as about 2,000,000 ohms, or, say, between 1,500,000 to 4,000,000 ohms. Such a resistance is shown in Fig. 5 as consisting of a narrow strip of ordinary heavy drawing paper GL, about one-eighth inch wide and one inch long and pain-ted with india ink. This paper sheet may be of a cardboard like Bristol board or thick paper. Either one or both sides of this paper sheet may be painted with the fluid ink. ln practice, the paper is painted in a large sheet by means of a brush, the ink being applied as a heavy coat and permit-ted to dry. After drying, the paper should not be bent or wrinkled.

zo It is cut into strips as shown in Fig. 5, being carefully handled to prevent bending or wrinkling, which is liable to alter the resistance which has been reached by proper painting or dipping in the ink. A suitable ink is Higginss Eternal Carbon ink.

Preferably the ends of the paper sheet resistance GL are clamped in copper clips C@ (Fig. 5). These clamps CC are preferably tinplated, to aid in the process step of Fig. 8. But clamps need not be used; and instead the ends of paper sheet GL may be painted with a rather thick mixture of water glass and powdered graphite, as a means of facilitating the effectiveness of the stepof the processshown in Fig. 8; and this graphite pain-t may be employed in considerable thickness with bulges or irregularities, for the same object.

As preliminary to the final assembly, the electrical resistance of Fig. 5 and the condenser of Figsl-S are placed alongside one another as shown in Fig. 6; both devices being of substantially the same length so that their ends lie alongside of one another in the same general vicinity.

Fig. 7 shows the next step in the manufacture, wherein the temporary assembly of Fig. 6 is shown as being inserted in a glass tube GT. The condenser C of this assembly (and Fig. 3) is cylindrical, and if employed alone without the resistance Gln. ln Fig. 7, the glass tube has sufficient internal diameter to provide spacefor the condenser C and resistance GL alongside one another. VThe ends F1, F2 of condenser G and the ends CC of resistance GL, in Fig. 7, are located in the vicinity of the ends of glass tube GT, both ends vof which are open. As shown in Fig. 7, the ends of both devices project beyond 60the ends of the tube, and this is preferred.

The next step .is to make permanent the assembly of Fig. 7. This step is shown in Fig.

8 where the assembly of the three parts,- p i. e., the tube, and the condenser and the re- 65 sistance inside the tube,#is placed so that one/set of ends of the three assembled parts (including one metal end, i. e., F1, of the` condenser), enters the depression shown in steel mold U, the depression being shaped in accord with the desired configuration of the ultimate ends of the completed device. This depression is filled with a molten soft metal such as Vfoods metal, which may be of composition resulting in melting at about the boiling point or water. Metals of'higher melting point may be used, such as solder; but alloys such as the well-known Ffoods metal are preferred because their lower boiling point avoids cracking` of glass tube m Ui or char-ring of the ends of resistance sheet GL. vVoods metal is preferred for use herein which has a composition resulting in its melting atabout C., 200 below the boiling point of water. rlubular condensercasing GT always, in accordance with the invention, is a strong structural element eX- isting as a unit before condenser C is inserted in it, as distinguished from a mere glaze which is applied to the outer surfaces of the condenser itself. The material of g which the tube is made, preferably glass, may be any other vitreous or vitrified material possessing the advantage here wherein the glazing at least at the surface, constitutes means of excluding moisture from the en- 9 closed condenser in addition to the electrical insulating property of the material of the tube in respect of the enclosed condenser, and the terminals 'thereof of opposite polarity and of conducting bodies outside the lube. As shown in the section of Fig. S the wall of the tubular casing is of substantial thickness relative to the size of the enclosed condenser, so as to compensate by way of thickness for the fragility of the vitreous or vitrihed material as compared with metal, the result being a structure which is sufficiently strong for its purpose altho of comparatively fragile material. Such thickness is co-operative with the methods shown, or equiv?.- lent methods, of securing the metal `erd structures NM with theends of the wall of the tubular casing, so as to reenforce the tube GL by the combination. with the relatively thick wall itself and that notwith- 1115 standing the structural fragility of the material of which the casing is composed, nevertheless the combination of WVM with the sufficiently thick casing wall not only doos not injure the latter, but on the other hand re- 120 enforces it, while the result is a permanent union of said parts. Such a union described seals the open ends of the tube against ingress of moisture, just as the glaze or` fitrif fied character of the casing-material seals the sides of the structure against of moisture to the contained condenser. An important advantage of this class of materials for casing Grl, in addition to its protection of the enclosed condenser, is that the vitrifaction of at least the external surface of the casing protect-s the casintgT itself from deterioration by atmospheric conditions,l so that altho thc tube itself not of metal yet Witaout any eXtra protection it can Withstand any service which does not subject the fragile material to severe mechanical. impacts. The inherent strains of the assembled structure are made harmless to the material of casing` GL by the means and methods disclosed. Furthermore the metal ends WM or their equivalents engage the condenser itself so to mechanically support it in position inside the casing, the ultimate support of course being the casing itself on which members WM are supported; but the Whole arrangement being such that casingT GL, altho of fragile material, can and does support both the metal end structures and the condenser itself Without any injury to the casing. Also the casing* as a Whole is made structurally strong, irrespective of the Weakness of the vitrilied maerial and irrespective of the supporting' of the condenser by the metal terminals XVM. by reason of the substantially thiclr wall of the vitriied casingr portion, in combination with the metal of terminals WM which terminals are secured to and supported b v (and thereby in'turn reenforce and strengthen as a Whole) the vitriied casing-portion GL.

The temporary assembly ot Fig. 7 has one end inserted in the molten metal NM as shown in Fi 8, Where it is held brieiiy until the soft metal cools and solidilies. The

- mold U may be surrounded with cold Water to ha .n operation. Thereupon tl Ve es semhly of Fig. Tis removed from the posi on of Fig. 8, the soft metal then being,r incorpo-` rated as shown at the top of Fig. 9, a permanent end terminal. ln Fig. 9 the entire apparatus unit is inverted from the position shown in 8, so that the top end of Fig'. 8 is inserted in mold U, the depression of which is avclain filled With the readily fusible 'metal XVM. to duplicate at the bottom of the device in Figr. 9, the end construction shown at the top of Fig. 9. f Any suitable materials .may be used for the molds, and in practice two-part molds indicated in Figs. S and 9 'are preferred, so that the parts ot' the mold can be removed laterally from the solidilied soft metal terminals. instead of removing the enclosed condenser from the mold.

The wWoods alloy or equivalent soft metal possesses the property of expanding upon cooling and solidifyinfr. The result therefore of the operations of Figs. S and 9 is that the soft metal end members contract tightlr around and grip the exterior of vitrif ed tube GT and seal the interior of the tube from the external atmosphere. (the tube itself being,r of moisture-proof insulatingF material), thereby preventing access of moisture to the paper resistance GL and the paper condenser C, preserving them of uniform humidity and constant electrical properties, as to resistance and capacity respectively. The projection of the nieta-l ends F1. F2 of the condenser C and the end CC of resistance GL beyond the open ends of glass tube GT assists the 'action of the metal NVM in effecting good mechanical and electrical Contact with. said elements; but the molten metal TVM Will enter up into the inside of vitrilied tube GT and surround the ends ofthe condenser and resistance, if there is sufficient space around the condenser and resistance and between them and tube GT), so as to adequately grip and make contact With said members at points inside the tube GT, irrespective of their grippino' by the metal on their parts which extend beyond the open ends of the tube. The soft metal by its eX- pansion upon solidification thereby is contri-acted around the proiectingr condenser foil tabs F1, F2 thereby tightly gripping them and making good electrical contact therewith,

constitiu';ini` the soft instal as a terminal of the conoenser, and holding' the condenser and the glass tube mechanically in permanent assembly. The soft metal when solidilied also tightly grips the ends of resistance GL` malring' good electrical Contact With it and holding the condenser and resistance in assembly with one anotlie i and holding each and both in permanent assembly with the vitrilied tube. The soft metal end members TVM also reinforce the ends of the vitrified tube; and by virtue of their good electrical connections with the condenser terminals and the resistance terminals, constAA rtecommon terminals for both the condenser and the resistance.

lNhen here both the condenser and resistance are located together in vitreous tube GT. the same permits dispensing with two. pairs of spring` holders, one pair for each of the condenser and resistance. (See Fig'. lO). The manner of combining the condenser and resistance lwhich is shown in Figs. 6-1O is preferred, i. e., Where said members are ranged alongside one anothe", as a matt-er of manufacturing; but, if des red, the resistance (of Fig. 5 or its equivalent Within the invention) may be combined With the condenser in the manner shown in F ig. 4, where the resistance GL shown in dotted lines is located at the center of the condenser cylinder, the sheets of the condenser being Wound around the electrical resistance. This temporary assembly of F ig. t, however, is less desirable than that of F G, because it in volres more time in Wrapping the condenser sheets around the electrical resistance; and in the form of Fig. l it is desirable to employ a third sheet of paper on top of the showing of Fig. l, for the purpose of insulating the resistance GL from foil sheet ,F14 (the inside foil sheet)Y of the rolled condenser. In either case, Fig. 4- or Fig. 6, the condenser and resistance are located in parallel with one another, and their ends also are Cil located in parallel With one another; and both have a length proportionate to that of the vitrilied tube GT oi" Figs. 7-8, such that the ends or" said elements lie in the vicinity et the open ends oit' said tube.

ln l0 the reactance C or" this invention is shown in service in a circuit between spring clips SC forming part oi' the stand shown; the pointed ends WVM ot' the device being suitable tor engagement in the holes in spring clips SC. @nly one oi those standards of Fig. l0, including the spring clips SG, is needed Vfor a given radio receiving set when the condenser C and resistance GL are included in vitriiied tube GT and held in the assembly by the metal end pieces Nh/l, the latter being preferably orn soft metal as described but permissively oiB other conducting material as terminals ot' the device and as means for retaining the elements of the device in assembly.

l particularly point out and distinctly claim the part, improvement, or combination which I claim my invention or discovery, as follows l. A capacity-resistance device comprising glass tube open at both ends; a sheet condenser rolled a-nd located inside said glass tube With its opposite potential conducting sheets projecting as tabs from the opposite ends of the rolled condenser and located in the vicinity ot the open ends of the glass tube; a paper sheet resistance inside said tube having an overall length substantially the same as that oi the condenser, its terminals being located in parallel with the projecting condenser tabs in the vicinity of the open ends of the glass tube; and two soft metal terminals contracted around the outside of rthe respective ends ot the glass tube, and contracted around and making good electrical contact With the Y tabs and resistance terminals, closing the ends of the glass tube and moisture-sealing the contained condenser and paper resistance 'from the external atmosphere, tightly gripping the tube, the condenser tabs and the resistance, and thereby holding all three in the assembly, reinforcing the ends ci the glass tube, and constituting common terminals for the condenser and resistance.

2. A capacity-resistance device comprising a tube ci insulating material having openings at both ends, a toil and paper sheet condenser rolled and located inside said tube, the opposite potential teils projectingas tabs 'from opposite ends of the rolled condenser and located in the vicinity of the open ends ot said insulator tube; a paper sheet resistance located in parallel with said condenser inside seid tube and having terminals located in parallel with the projecting foils or'l the condenser; and tWo sott metal terminals contracted around the outside of the respective ends ot the insulating tube, and contracted around and making good electrical contact With the toil tabs and resistance terminals, closing the ends of the insulating tube and moisturesealing the contained condenser and paper resistance from the external atmos-.

phere, tightly gripping the tube, the condenser tabs and the resistance,iand thereby holding all three in the assembly, reinforcing the ends oit the insulating tube, and constituting common terminals for the condenser resistance.

3. A, capacity-resistance device comprising a tube oic insulating material open at both enos, a sheet condenser rolled and located inside said insulating tube with its opposite potential conducting sheets projecting as tabs from the opposite ends of the rolled condenser and located'in the vicinity of said open tubeends; an electrical resistance having an overall length substantially the same as that of the condenser, its ends being located in parallel with the condenser tabs in the vicinity of the open ends orp the insulating tube; and tvvo soft metal 'terminals contracted around the outside of the respective ends of the insulating tube, and contraci'zetL around and making good electrical contact with the foil tabs and rcsistance terminals, closing theends of the insulating tube and moisture-sealing the contained condenser and paper resistance from the external atmosphere, tightly gripping the tube, the condenser tabs and the resistance,

and thereby holding all three in the assembly, reinforcing the ends oit the insulating tube, and constituting common terminals for the condenser and resistance,

fl. A capacity-resistance device comprising a tube of insulating material open at both ends; a sheet con-denser rolled and located inside said insulating tube with its opposite potential conducting elements projecting as tabs from the opposite ends of the rolled condenser and located in the vicinity of said open tube ends; an electrical resistance having an over all length substantially the saine as that of the condenser, its ends being located in parallel With the condenser tabs in the vicinity ot the open ends ot the insulating tube; and tivo metal end members extending around the outside of the respective ends ot the insulating` tube and electrically and mechanically connected With the condenser tabs and resistance ends, said end members closing the ends of the tube and holding` in assembly the tube, condenser and resistance, reinforcing the ends of the tube and constituting common circuit terminals for the condenser and resistance.

ln testimony whereof l hereunto aiiiX my signature.

lWlLLlAll/l M. BAILEY. 

